This invention relates to improvements in fluid delivery systems and relates particularly to improvements in such systems which may be used for firefighting purposes, dust laying in mines and other environments, agricultural applications, industrial cleaning and other applications.
While the invention is suitable for any of the applications referred to above, and others, it will be described herein in relation to its application to firefighting. It will be appreciated, however, that the invention is not so limited and aspects of the invention which may need to be modified for its application in other areas will be apparent to those skilled in the art.
Water cannon used in firefighting, and in other applications, may be mounted at any appropriate location including on firefighting vehicles. Thus, it is known to mount water cannon on the cabins of firefighting vehicles, such cannons being remotely controlled from within the vehicle cabin. Generally, the cannon is mounted so that the director nozzle is movable both in a vertical and horizontal plane to direct fluid issuing from the nozzle in the desired direction. To facilitate such movement, parts of the water cannon assembly must be moveable relative to each other.
In one particular form of water cannon, the cannon structure is formed of pipe work which is adapted to be mounted in the desired location, such as on a vehicle cabin, the pipe work being connected to a supply of fluid, and the pipe work being relatively moveable so that a nozzle on its end may be directed in an appropriate, desired direction. With this arrangement, the movement of parts of the pipe work relative to each other requires the use of one or more fluid tight bearings.
Such fluid type bearings may involve the use of radially extending bearing surfaces, which may incorporate needle, roller or ball bearings, and axially extending sealing surfaces which incorporate a sealing medium, such as one or more O-rings or other sealing material acting between relatively movable, radially spaced, axially extending cylindrical surfaces. Such known bearings provide minimum stability and support for equipment attached thereto.
It is therefore desirable to provide an improved water delivery system incorporating a modified form of bearing connecting relatively moveable pipe sections.
It is also desirable to provide an improved bearing assembly for relatively movable pipe sections which is relatively simple in construction, is rugged and durable in use and is easily maintained.
It is also desirable to provide an improved bearing assembly for relatively movable pipe sections in a fluid delivery system which incorporates driving means for relatively moving one of the pipe sections.
It is also necessary that movement of the nozzle be effected by an appropriate power source. It has been known to utilise air compressors fitted to firefighting vehicles to provide pneumatic control systems for the water cannon. Alternatively, other known systems use the existing vehicle hydraulic system to obtain a supply of hydraulic power for operation of the water cannon.
However, the use of the vehicle hydraulics in a water cannon system has certain inherent disadvantages including potential contamination to the hydraulic fluid in the vehicle hydraulic system, constant oil flow and pressure through that system which may shorten the life of components, relatively complicated xe2x80x9cset upxe2x80x9d in providing the necessary hydraulic lines and connectors, and significant vehicle down time when water cannon servicing needs to be performed.
It is therefore desirable to provide an improved water delivery system which obviates some of the disadvantages of the systems currently known and available.
It is also desirable to provide an improved fluid delivery system which is versatile, may be fitted in any appropriate location, including on vehicles and the like, does not require the use of existing hydraulic or pneumatic lines, and is able to be retrofitted, where necessary.
According to one aspect of the present invention there is provided a bearing assembly for relatively moveable pipe sections in a fluid delivery system, said assembly comprising a main body adapted to be connected to one end of one pipe section, the main body having a coaxial seat to receive a first annular bearing member, and a coaxial groove to receive an annular seal member, an annular center swivel section having on one radial face a coaxial seat to engage said first bearing member and having a similar coaxial seat on an opposed radial face to receive a second annular bearing member, said swivel section including an annular, axially extending boss extending away from said main body, said boss being adapted to be connected to one end of a second pipe section, and a bearing end cap adapted to engage around said second pipe section and be fastened to said main body sandwiching said swivel section and bearing members, said end cap having a seat for said second bearing member, and a second annular seal member disposed between said end cap and said swivel section.
In a preferred form of the invention, the center swivel boss extends through the opening in the end cap and is closely spaced therefrom. The boss provides rigidity for the center swivel as well as providing for the securement of the second pipe section.
In one form of the invention, the main body is formed on its outer surface with gear teeth by which the body and its associated first pipe section is able to be rotated about the axis of the bearing relative to the swivel section and the second pipe section.
In a preferred form of the invention, the end cap is secured to the main body by means of axially extending bolts. The main body may be secured to the first pipe section by welding or the like or by use of a screw thread formed in the main body and on the end of the pipe section. Locking means may be used to securely lock the body to the pipe section as necessary.
Similarly, in a preferred form of the invention, the swivel section is secured to the second pipe section by welding or the like or by the use of cooperating screw threads with an appropriate lock nut or other locking means.
Preferably, the bearing members each comprise annular thrust rings with substantially parallel, radial faces which engage the respective main body, swivel section and end cap. While the first bearing member is preferably formed as a one piece thrust ring, the second bearing member may be formed as a split thrust ring to facilitate assembly of the bearing member onto a second pipe section which is welded or otherwise secured to the swivel section, particularly during maintenance and replacement of that bearing member.
Preferably, the end cap is provided with a dust seal slot in an inner cylindrical surface which is adjacent the surface of the second pipe section. An appropriate dust seal is located in the dust seal slot to minimise the ingress of foreign matter.
The bearing assembly of the present invention provides a rigid yet easily rotatable bearing structure for two pipe sections which may form the pipe work associated with a water cannon or the like. Such devices are commonly mounted on the cabins of vehicles and, as such, are subject to substantial vibration and lateral and bending forces which are concentrated at the bearing connection between the pipe sections. The bearing assembly of the present invention, incorporating the center swivel with the elongated, axially extending boss which passes through the end cap, provides the necessary rigidity and stability for a cannon system.
A further aspect of the present invention is the provision of a hydraulic water cannon kit adapted to be mounted at any appropriate location, including a vehicle cabin or other location on a vehicle, or at any fixed location. The system of the invention draws power from any electrical supply, including a vehicle electrical supply, and includes electrically driven hydraulic pumps to supply hydraulic motors which control the system, including rotation of the pipe work.
The water cannon, or similar equipment, is supplied with water from a storage system using pumps to develop the necessary head. Two bearing assemblies are incorporated into the water cannon pipe system whereby the water cannon nozzle is able to be moved in both the horizontal and vertical planes. Hydraulic motors are associated with each bearing whereby the appropriate pipe section is able to be rotated relative to its associated section to produce the necessary movement of the nozzle. Alternatively, hydraulic cylinders may be used in place of hydraulic motors where the angle of movement is limited.
An electric joy stick control is provided at an appropriate location, such as in a vehicle cabin, whereby movement of the water cannon nozzle is able to be controlled in a known manner.
In order that the invention is more readily understood, embodiments will now be described with reference to the accompanying drawings.